A new mass spectrometric technique for the investigation of microscale chemical reactions of surface bound biologically interesting molecules will be explored. The technique involves essentially nondestructive ion bombardment mass spectrometric analysis of a solid surface film of the biological material of interest prior to and after chemical modification of the film. The long-term objective of the project is to refine and develop the new method to provide a general means for the rapid, untrasensitive and highly specific determination of structural detail and chemical behavior of complex biologically interesting molecules. Specifically, it is proposed: to extend the range of reactions which have been carried out to date with both gas and condensed phase reagents and to optimize conditions for carrying out these reactions; to engineer and investigate surfaces which have the desired properties with respect to binding and to carrying out reactions on biological molecules; to explore fundamental details relating to surface absorption of biomolecules and chemical reactions of surface bound species. It is also proposed to develop methods whereby very small amounts of separated peptides and proteins may be transferred from electrophoretic gels to solid surfaces for microchemical reaction and/or direct mass spectrometric analysis. An economical and efficient method for performing 252C fission fragment ionization time-or-flight mass spectrometry/mass spectrometry (TOF-MS/MS) will be developed and explored. The technique involves the correlated detection of fragments pairs arising from metastable fragmentation of energetically excited precursor ions in the mass spectrometer flight-tube. The long term objective of this portion of the project is to develop highly sensitive MS/MS means for obtaining detailed structural information from high molecular wight biomolecules. Specifically, it is proposed: to determine the analytical utility and the properties of the new TOF-MS/MS configuration for the structural determination of polypeptides; to determine the presently unknown fragmentation behavior of large energetically excited ions produced from biomolecules with molecular weights in the range 5,000-25,000 daltons; to elucidate the presently unknown fragmentation paths of multiply protonated proteins with molecular weights in the range 5,000-25,000 daltons.